Low-temperature distillation of fuels by direct contact with reheated distillate vapors



Aug.'31, 1943 H. LANTZ Filed June 23, 1937 V4 III/I/I/ LOW TEIPERATURB DIS'I'ILLATION OF FUELS BY DIREQT CONTACT IITH REHEATED DISTILLA'IE VAPORS 7a (a DBMS/N6 INVENYOR 7N6 HENRI LANTZ 87- k 6". laroluunzs mama Aug. 31,19

UNITED LOW-mm IJIS'IIIJIA'I'ION OI FUELS BY DIR-I01 CONTACT WITH BIIIIBA'IED DIS'I'ILLATE VAPORS HenriLantmParis,

Chimiouedela France, casino: to Boelete l Granule Paroisae (Aaotel:

ProduitoChimiqIesLPariaFranoe Application June 2:, 1931, Serial No. uaosz In France June 30, 1938 Section 8, Public Law 890, August 8, 1946 Patent expires June 30, 1956 1 This invention relates to'the low temperature distillation of fuels, and more particularly to a plant which is particularly simple to operate and which enables high quality oils and tars to be produced by low temperature distillation of coal, lignite, bituminous shales and mineral or organic materials. The distilling retort comprises a vertical chamber containing the material to be distilled, the

horizontal section of said chamber being preferably rectangular, while its vertical section may be rectangular or may be flared outwardly towards the bottom so as to facilitate the descentof the material by gravity.

The twoopposite vertical faces of the retort (or, in the case of a retort having an oval or circular section, two opposite vertical bands) are provided with perforations or orifices disposed in such a manner as to permit the circulation of the gas which will be described hereinafter, while retaining the materials contained in the retort; in particular, these orifices may have the form of Venetian blind slits.

Each of the perforated faces communicates with a chamber which may be partitioned oil in the vertical direction or in the horizontal direction. One of these chambers serves for the intro.- ductlon and the other for the evacuation of the heating gas, and for this purpose they are furnished with a convenient number of suitably disposed orifices which are connected to the circulation system described hereinafter.

The upper part of the retort is provided with a substantially gas-tight device which permits the introduction of the materials to be distilled, while its lower part is fitted with a device'f or discharging the residues.

The distillation is carried out in this retort by causing a current of pre-heatedgas to circulate through the material from one perforated face to the opposite face; by virtue of the-partitioning of the chambers it is possible eitherto introduce .of the circulating gases to be obtained.

Instead of being formed of a prism or a cyl- 3 Chin. (Cl. 202-16) inder having perforations on two opposite faces, the retort may be formed by two coaxial prisms or cylinders each carrying perforations, when the circulation of the heating gas is then effected horizontally from one wall to the other.

The upper closure means of the retort may be dispensed with provided that a narrowed portion be provided between the pre-heating zone and the heating zone, and that the pressures on either side of this narrowed portion be regulated in such a manner that the circulation of gas from one zone to the other is practically nil.

This arrangement renders charging easier and enables any entry of air into the distillation zone to beprevented. o The device for discharging-the residues may comprise a pan filled with water into which the hot residues gradually penetrate; the steam which is formed rises into the retort and mixes with the circulating gases;- owing to the presence of this steam, the deposition of carbon caused by heating the distillation gases in the heat exchanger is diminished in very substantial fashion.

It is also possible to restrict the arrangement to the introduction of a limited quantity of water into the apparatus for discharging the distillation residues. f

In order more clearly to understand the invention, reference is made to the accompanying drawing, which illustrates diagrammatically and by way of example, one embodiment thereof particularly adapted to the distillation of bituminous shales.

In said drawing- The retort C has on two opposite faces the through the feed hopper T and the residue is discharged at U.

In the upper part of the retort the shale undergoes a preheating up to about 225,-during which only inert or harmful gases (CO2 and H28) are liberated which are not collected; on descending, the shale netrates into the actual distillation zone where it encounters a current of gases circulating horizontally between two opposite walls of the retort; this hot gas arrives through the pipe I into the chamber 2, which distributes it over the whole height of the inlet slats, it traverses the shale and passes out through the chambers la, 3b and 3c and the main pipe 4; the flow in each stage is regulated by the dampers Ra, Rb, Re: the gas is taken back by the fan V which passes it into the heat exchanger 6 fitted in a furnace F heated by the gases of the fire-box G. A poriOll 0f the gas, corresponding to the vapours 3 evolved from th distillation of the shale, is evacuated through the pipe. 5 and passed on to the condensing plant.

The combustion gases from the furnace F traverse a waste-heat boiler E where their temperature, if not lowered enough by the heat exchanger 6, will be lowered to 250 C. Pipe 9 conveys the gases into the chamber H) which surrounds the upper part of the retort; these combustion gases enter the retort through the slats, heat the shale and are evacuated to th exterior through the pipe I I and the fan V.

By causing a portion of the combustion gases to recirculate through pipe 8 and fan V2, accurate regulation of the temperature of the furnace F and, in consequence, of the heating of the gases of the distillation circuit becomes possible.

The fire-box G is fed either with a solid fuel or with the residual gas obtained at the outlet of the oil condensing plant.

If the materials have a tendency to agglomerate during the distillation, it will be necessar to install a system of agitators inside the retort with the object of maintaining the material in a divided state; use will be made, for example, of

vertical or horizontal shafts fitted with arms or I blades in screw form.

I claim:

1. A continuous process of destructively distilling carbonaceous material at a low temperature comprising: feeding the carbonaceous material through an unobstructed vertical column, first downwardly intoand through a preheating zone therein, thence downwardly into and through a distilling zone therein; withdrawing distillation products from one side of said distilling zone; passing a portion of said distillation products to a condensing zone; recycling the remaining portion of said distillation products through a heat exchange zone to reheat them and introducing said reheated distillation products into the other side of said distillation zone in direct contact with the material to be distilled; burning a fuel; passing the hot products of combustion of said fuel into said heat exchange zone in heat exchange relation with the recycled'distillation products; discharging the combustion products from said heat exchange zone in heat exchange relation with a cooling medium to further cool the combustion products; passing a portion of the so-cooled combustion products into the preheating zone into direct contact with the carbonaccousmaterial to preheat the same; and recycling another portion of the so-cooled combustion products to the heat exchange zone, mixing the same with fresh hot combustion products prior to introduction of the latter into the heat exchange zone; and adjusting the fiow of the reheated distillation products through the distillation zone and the flow of the combustion products through the preheating zone so as to maintain substantially the same pressure in both said zones, whereb any passage of gas from one zone to the other is prevented and the whole of the heat used in the process adjusted by adjusting the recycled part of the flue gases,

. ,4 tilling zone; passing a portion of said distillation products to a condensing zone; recycling the remaining portion of said distillation products through a heat exchange zone to reheat them and introducing said reheated distillation products into the other side of said distillation zone in direct contact with the material to be distilled; burning a fuel; passing the hot products of combustion of said fuel into said heat exchange zone in heat exchange relation with the recycled distillation products; discharging the combustion products from said heat exchange zone in heat exchange relation with a cooling medium to fur- .ther cool the combustion products; passing a portion of the so-cooled combustion products into the preheating zone into direct contact with the carbonaceous material to preheat the same; and recycling another portion of the so-cooled combustion products to the heat exchange zone, mixing the same with fresh hot combustion products prior to introduction of the latter into the heat exchange zone; and adjusting the fiow of the reheated distillation products through the distillation zone and the flow of the combustion products through the preheating zone so as to maintain substantially the same pressure in both said zones, whereby any passage of gas from one zone to the other is prevented and the whole of the heat used in the process is adjusted by adjusting the recycled part of the hue gases through the heat exchanger, discharging the material through a water seal for cooling said material and thereby producing steam, which mingles with the gases in the distilling zone.

3. A continuous process of destructively distilling carbonaceous material at a low temperature comprising: feeding the carbonaceous material through an unobstructed vertical column, first downwardl into and through a preheating zone therein, thence downwardly into and through a distilling zone therein; withdrawing distillation products from one side of said distilling zone; passing a portion of said distillation products to a condensing zone; recycling the remaining portion of said distillation products through a heat exchange zone to reheat them and introducing said reheated distillation products into the other side of said distillation zone in the form of a plurality of individually controlled streams in direct contact with the material to be distilled and to successive sections of the material whereby heating in the distillation Zone may be adjusted separately for each section; burning a fuel; passing the hot products of combustion of said fuel into said heat exchange zone in heat exchange relation with the recycled distillation products; discharging the combustion products from said heat exchange zone in heat exchange relation with a cooling medium to further cool the combustion products; passing a portion of the so-cooled combustion products into the preheating zone into direct contact with the carbonaceous material to preheat the same; and recycling another portion of the so-cooled combustion products to the heat exchange zone, mixing the same with fresh hot combustion products prior to introduction of the latter into the heat exchange zone; and adjusting the flow of thereheated distillation products through the distillation zone and the flow of the combustion products through the preheating zone so as to maintain substantially the same pressure invboth said zones, whereby any passage of gas from one zone to the other is prevented and the. whole. of the heat useddn the process is adjusted by adjusting Number the recycled part of the flue gases through the 1,489,378 heat exchanger. 1,528,600

- 1,538,954 HENRI LANTZ. 5 1,557,077 1,738,202 REFERENCES CITED 1 05 109 The following references'are of record in the fileof this patent. 10 1,937,552

UNITED STATES PATENTS 2,131,702 7 2,167,099 Number Name Date 522,357 Sternberg July 3, 1894 878,490 Aylesworth et 21. Feb. 11, 1908 Number 1,079,093 283,259

Ay1esworth et a1. Nov. 18, 1913 Name Date Wood Apr. 8, 1924 Bowater Mar. 3, -1925 Rosenthal May 26, 1925 Moetheli Oct. 13, 1925 Plantinga Dec. 3, 1929 Runge et a1. May 12, 1931 Trumble Dec. 15, 1931 Herrick Dec. 29, 1931 Davis, Jr. Dec. 5, 1933 Berry Sept. 27, 1938 Benezech July 25, 1939 FOREIGN PATENTS Country Date Great Br1ta1n, Jan. 2, 1928 

